A school resource officer in Kentucky placed handcuffs on a third-grade boy with disabilities as he cried, according to a video released on Monday by the American Civil Liberties Union.

The ACLU released the video along with a lawsuit filed against the Kenton County Sheriff's Office in Covington, Ky., due to numerous incidents. The ACLU alleges that Kenton County Deputy Sheriff Kevin Sumner, a school resource officer, shackled an 8-year-old and a 9-year-old with their hands behind their...